我正在运行下面的C#代码，它计算光流图，并在游戏过程中将其保存为PNG，使用Unity和VR头戴式设备，强制上限为90 FPS。如果没有这段代码，项目将以90 FPS平稳运行。要在同一个项目上运行这段代码，始终保持80 FPS以上，我不得不使用WaitForSeconds（0.2f），但是理想的情况是为游戏的每一帧计算并保存光流图，或者至少延迟更低，大约0.01秒。我已经在使用AsyncGPUReadback和WriteAsync了。

*主要问题：如何进一步加快此代码的执行速度？

• 附带问题：有没有办法把计算出的光流图作为连续的行转储到CSV文件中，这样就可以写在一个文件中，而不是为每个图创建一个单独的PNG？或者这会更慢吗？

using System.Collections;
using UnityEngine;
using System.IO;
using UnityEngine.Rendering;

namespace OpticalFlowAlternative
{

    public class OpticalFlow : MonoBehaviour {

        protected enum Pass {
            Flow = 0,
            DownSample = 1,
            BlurH = 2,
            BlurV = 3,
            Visualize = 4
        };

        public RenderTexture Flow { get { return resultBuffer; } }

        [SerializeField] protected Material flowMaterial;
        protected RenderTexture prevFrame, flowBuffer, resultBuffer, renderTexture, rt;

        public string customOutputFolderPath = "";
        private string filepathforflow;
        private int imageCount = 0;

        int targetTextureWidth, targetTextureHeight;

        private EyeTrackingV2 eyeTracking;

        protected void Start () {
            eyeTracking = GameObject.Find("XR Rig").GetComponent<EyeTrackingV2>();
            targetTextureWidth = Screen.width / 16;
            targetTextureHeight = Screen.height / 16;
            flowMaterial.SetFloat("_Ratio", 1f * Screen.height / Screen.width);

            renderTexture = new RenderTexture(targetTextureWidth, targetTextureHeight, 0);
            rt = new RenderTexture(Screen.width, Screen.height, 0);

            StartCoroutine("StartCapture");
        }

        protected void LateUpdate()
        {
            eyeTracking.flowCount = imageCount;
        }

        protected void OnDestroy ()
        {
            if(prevFrame != null)
            {
                prevFrame.Release();
                prevFrame = null;

                flowBuffer.Release();
                flowBuffer = null;

                rt.Release();
                rt = null;

                renderTexture.Release();
                renderTexture = null;
            }
        }

       IEnumerator StartCapture()
        {
            while (true)
            {
                yield return new WaitForSeconds(0.2f);
                
                ScreenCapture.CaptureScreenshotIntoRenderTexture(rt);
                //compensating for image flip
                Graphics.Blit(rt, renderTexture, new Vector2(1, -1), new Vector2(0, 1));

                if (prevFrame == null)
                {
                    Setup(targetTextureWidth, targetTextureHeight);
                    Graphics.Blit(renderTexture, prevFrame);
                }

                flowMaterial.SetTexture("_PrevTex", prevFrame);

                //calculating motion flow frame here
                Graphics.Blit(renderTexture, flowBuffer, flowMaterial, (int)Pass.Flow);
                Graphics.Blit(renderTexture, prevFrame);
                
                AsyncGPUReadback.Request(flowBuffer, 0, TextureFormat.ARGB32, OnCompleteReadback);
            }
        }

        void OnCompleteReadback(AsyncGPUReadbackRequest request)
        {
            if (request.hasError)
                return;

            var tex = new Texture2D(targetTextureWidth, targetTextureHeight, TextureFormat.ARGB32, false);
            tex.LoadRawTextureData(request.GetData<uint>());
            tex.Apply();

            WriteTextureAsync(tex);
        }

        async void WriteTextureAsync(Texture2D tex)
        {

            imageCount++;
            
            filepathforflow = customOutputFolderPath + imageCount + ".png"; 
            var stream = new FileStream(filepathforflow, FileMode.OpenOrCreate);
            var bytes = tex.EncodeToPNG();
            await stream.WriteAsync(bytes, 0, bytes.Length);
        }

        protected void Setup(int width, int height)
        {
            prevFrame = new RenderTexture(width, height, 0);
            prevFrame.format = RenderTextureFormat.ARGBFloat;
            prevFrame.wrapMode = TextureWrapMode.Repeat;
            prevFrame.Create();

            flowBuffer = new RenderTexture(width, height, 0);
            flowBuffer.format = RenderTextureFormat.ARGBFloat;
            flowBuffer.wrapMode = TextureWrapMode.Repeat;
            flowBuffer.Create();
        }
    }
}